(1) Field of the Invention
The present invention pertains to a spacing tool for use with air conveyors. In particular, the present invention relates to a spacing tool that can be used for calibrating the spacing between the guide rails of an air conveyor that transports plastic bottle containers along a conveying path defined by a pair of flanges and the guide rails.
(2) Description of the Related Art
Air conveyors are typically employed in the rapid transport of empty plastic bottle containers. FIG. 1 is an end elevational view of a typical prior art air conveyor apparatus. In FIG. 1, the air conveyor apparatus is indicated generally by the reference character C. The air conveyor apparatus C is shown with a plastic bottle container, indicated generally by the reference character B. The bottle container B is of the type having a narrow neck portion N, an annular rim or neck ring R around the neck portion N, and a body J below he neck portion N.
The air conveyor C includes a pair of flanges F that are spaced laterally from one another defining an elongate slot between the flanges. The spacing between the flanges F is sufficiently large to enable the neck portion N of the bottle container B just below the neck ring R to pass through the spacing with the bottle container suspended from upper surfaces U of the flanges F by the neck ring R engaging on the upper surfaces U. A series of air ducts D are positioned along the length of the conveyor C adjacent the flanges F. An air plenum of the air conveyor (not shown) supplies a flow of air to the air ducts D. The air ducts D are oriented so that air ejected from the ducts will contact the plastic bottle containers B, thereby pushing the bottle containers B along the pathway defined by the flanges F with the neck rings R of the bottle containers B sliding along the upper surfaces U of the spaced flanges F.
Preferably, such air conveyors transport a plurality of bottle containers in closely spaced succession and at a substantial speed. A typical air conveyor is constructed with both straight sections and curved sections in order to transport the succession of bottle containers from one area to another. Air conveyors often have guide rails for limiting the side-to-side movement of the bottle containers being conveyed. The air conveyor C shown in FIG. 1 includes guide rails G positioned below the flanges F on opposite sides of the conveying path defined by the flanges F. The guide rails G are spaced further apart from each other than are the flanges F to allow the width of a bottle container body J suspended from the flanges F to pass easily between the guide rails G. The guide rails G limit the side-to-side movement of the bottle containers B conveyed by the air conveyor C and thereby limit the extent to which the bodies J of the bottle containers can swing outwardly or transversely from the conveying path, e.g., when the air conveyor rounds a curve. Such guide rails help to avoid a bottle container neck or neck ring becoming jammed in the slot between the support flanges.
With a typical air conveyor being capable of transporting a large succession of plastic bottle containers at a considerable rate of speed, spacings between the support flanges and guide rails must be precise in order to ensure efficient operation. Thus, the spacings between the support flanges and guide rails must be calibrated precisely during initial assembly of the air conveyor apparatus, and must also be recalibrated periodically in order to maintain the proper spacing. In addition, the spacings of the support flanges and guide rails must be calibrated each time the conveyor is to be used to transport bottle containers of different dimensions.
Thus, a calibration tool is needed for setting and maintaining the proper spacing between the support flanges and guide rails of an air conveyor apparatus. It is desirable that the tool have a simple construction that allows it to be moved into position between the support flanges and/or guide rails at virtually any point along the length of the conveyor.